Transient Flow Behavior of Crude Oil-Alcoflood Polymer Emulsions

The transient flow behavior of crude oil-Alcoflood polymer emulsions is investigated in this study. A wide range of crude oil, 0-75 vol %, and polymer concentrations, 0-10(4) ppm, were employed to study the transient flow behavior in terms of viscosity and shear rate. Three different Alcoflood polymers were tested in this investigation, i.e., AF1235, AF1275, and AF1285. A 1 vol % Triton X100 was used as an emulsifying agent to form a stable emulsion of crude oil-Alcoflood polymer. Constant shear rates of 5, 25, and 50 s(-1) were applied for 300 s to measure the emulsion viscosity of all examined samples. There was no transient response reported for polymer concentration of <= 1000 ppm. The polymer concentration and shear rate influenced the transient flow behavior of polymer aqueous solution. Aqueous solutions of AF1275 and AF1285 show rheopectic behavior, whereas the aqueous solution of AF1235 provides a slight thixotropic flow. The emulsion viscosity increases significantly with crude oil concentration without modifying the nature of the transient flow behavior and transient period of the polymer aqueous solutions.